The present invention relates to a detent for a valve. More particularly the invention relates to a resilient detent that is positioned circumferentially around a slideable valve body in a hydraulic valve. In prior art hydraulic valves there has frequently been a need to maintain the hydraulic valve at a select position during the operation of the valve. The valve is usually held in the select position to allow a hydraulic cylinder associated with the valve to complete its stroke in one direction.
To accomplish the maintaining of the valve in a predetermined position a detent is brought to bear against the slideable valve body in the valve. The detent is frequently a pin that is spring loaded or biased towards the valve body. The valve body is adapted with an aperture for receiving the pin of the detent. When the valve body is positioned in the desired location the aperture will be in alignment with the pin of the detent. The pin will then be caused to engage the aperture by the biasing force or the spring loading on the pin. Accordingly, the pin will engage the aperture and maintain the valve body in the desired location.
When it is desired to move the valve body from the preselected position a force will have to be applied to the valve body sufficient to cause the pin of the detent to be disengaged from the aperture in the valve body. Normally, this force will have to be sufficient to overcome the biasing force of the spring loading and cause the pin to move away from the aperture in the valve body. Once the pin has been disengaged from the aperture the valve body will be free to move until the valve body is again put in a position where the aperture in the valve body is in alignment with the pin of the detent whereby the pin will engage the aperture and maintain the valve body in the desired position.
The above-described valve detents are difficult to position in the housing for the valve. The pin must be positioned so that it is capable of moving in a direction substantially perpendicular to the surface of the valve body. The pin of the detent must also be spring loaded or biased towards the valve body. Accordingly, a cavity or other suitable area must be provided in the housing for the valve to properly position and bias the pin of the detent towards the valve body. The aperture in the valve body must also be carefully positioned so that it will matingly align with the spring loaded pin of the detent. If the aperture is not properly positioned the detent will not be able to engage the aperture or the detent will engage the aperture and not hold the valve body in the preselected position.
The above-described prior art detents are expensive to make and difficult to position within the body of the valve. Frequently there is not a good location in the valve housing where the detent can be positioned and engage an appropriate part of the slideable valve body. The problems associated with positioning the detent become more significant if the valve is small. In addition, the prior art detents are difficult to properly maintain and service within the valve. Frequently it is necessary to completely disassemble the entire valve arrangement to get access to the detent assembly. It is also necessary that the detent arrangement found in the prior art be manufactured very carefully and assembled very carefully so that the detent will work properly in connection with the valve body. Further, these prior art detents are expensive to manufacture and assemble, and significantly increase the price of any valve with which they are associated.